1. Field of the Invention
Disclosed herein are pedicle screws related to the field of orthopedic surgery. More particularly, certain embodiments disclosed herein relate to a pedicle screw and methods of use.
2. Description of the Related Art
Spinal fusion encompasses a surgical technique in which two or more vertebrae are connected together. This technique may be used for multiple indications, including abnormal spinal curvature (e.g., scoliosis) and weakening or injuring of the vertebrae or spinal disc.
In some instances, this process is accomplished and/or supplemented using a plurality of screws implanted into the pedicle of adjacent vertebrae and joined together by a series of one or more rods. The pedicle screw may have an enlarged head that interfaces with a housing having a corresponding cavity, thus allowing for a range of polyaxial articulation between the screw and the housing. After the pedicle screw is implanted into bone, a rod may be placed in the housing, and a set screw may delivered into engagement with the housing, applying a downward force on the rod to hold the assembly together. This downward force is also supposed to cause engagement of the head of the pedicle screw relative to the housing, to thereby fix the position of the pedicle screw relative to the housing and prevent disengagement. However, prior pedicle screw designs may not provide sufficient force to hold the pedicle screw relative to the housing to fix their relative locations and/or prevent disengagement.